/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | foam-extend: Open Source CFD
   \\    /   O peration     | Version:     4.1
    \\  /    A nd           | Web:         http://www.foam-extend.org
     \\/     M anipulation  | For copyright notice see file Copyright
-------------------------------------------------------------------------------
License
	This file is part of foam-extend.

	foam-extend is free software: you can redistribute it and/or modify it
	under the terms of the GNU General Public License as published by the
	Free Software Foundation, either version 3 of the License, or (at your
	option) any later version.

	foam-extend is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with foam-extend.  If not, see <http://www.gnu.org/licenses/>.

Class
	Foam::linearInterpolationWeights

Description

SourceFiles
	linearInterpolationWeights.C

\*---------------------------------------------------------------------------*/

#ifndef linearInterpolationWeights_H
#define linearInterpolationWeights_H

#include "interpolationWeights.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{


class linearInterpolationWeights
:
	public interpolationWeights
{

private:

	// Private data

		//- Cached index in samples from previous invocation
		mutable label index_;

	// Private Member Functions

		//- Get weights of i and i+1 to calculate integration from t to
		//  samples_[i+1]
		Pair<scalar> integrationWeights
		(
			const label i,
			const scalar t
		) const;

public:

	//- Runtime type information
	TypeName("linear");

	// Constructors

		//- Construct from components
		linearInterpolationWeights
		(
			const scalarField& samples
		);


	//- Destructor
	virtual ~linearInterpolationWeights()
	{}


	// Member Functions

		//- Calculate weights and indices to calculate t from samples.
		//  Returns true if indices changed.
		virtual bool valueWeights
		(
			const scalar t,
			labelList& indices,
			scalarField& weights
		) const;

		//- Calculate weights and indices to calculate integrand of t1..t2
		//  from samples. Returns true if indices changed.
		virtual bool integrationWeights
		(
			const scalar t1,
			const scalar t2,
			labelList& indices,
			scalarField& weights
		) const;
};


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace Foam

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#endif

// ************************************************************************* //
